Elderly (65+) Native Hawaiian, Filipino, and Japanese men and Filipino women have a higher risk of diabetes-related potentially preventable hospitalizations than Whites even when demographic factors and the higher diabetes prevalence in these populations is considered. The study objective was to determine if similar disparities are seen among the non-elderly (< 65). We used discharge data for all non-maternity hospitalizations by working-age adults (18-64 years) in Hawai'i from December 2006 to December 2010. Annual diabetes-related preventable hospitalization rates (by population diabetes prevalence) were compared by race/ethnicity (Japanese, Chinese, Native Hawaiian, Filipino, and White) and gender. Adjusted rate ratios (aRR) were calculated relative to Whites using multivariable models controlling for insurer, comorbidity, residence location, and age. After adjusting for ethnic-specific prevalence of diabetes and demographic factors, preventable hospitalizations rates were significantly higher for Native Hawaiians males (aRR:1.48; 95%CI:1.08-2.05) compared to Whites, but significantly lower for Chinese men (aRR:0.43;95%CI:0.30-0.61) and women (aRR:0.18;95%CI: 0.08-0.37), Japanese men (aRR:0.33;95%CI: 0.25-0.44) and women (aRR:0.34; 95%CI:0.23-0.51), and Filipino men (aRR:0.35;95%CI:0.28-0.43) and women (aRR:0.47;95%CI: 0.36-0.62). Rates for Native Hawaiian females did not differ significantly from Whites. Disparities in diabetes-related preventable hospitalizations were seen for working-age (18-64) Native Hawaiian men even when their higher population-level diabetes prevalence was considered. Further research is needed to determine factors affecting these disparities and to develop targeted interventions to reduce them. Significantly lower preventable hospitalization rates were seen among Asian groups compared to Whites. A better understanding of these findings may provide guidance for improving rates among Asian elderly as well as other non-elderly groups with disparities.